Sistani was born in 1930 to a family of religious clerics, his father was Muhammad Baqir al-Sistani. Sistani himself claims to have been born in Mashhad, Iran, however there are disputes whether or not he was born in Mashhad or in Sistan then moved to Mashhad as a child due to Iran not issuing birth certificates in its eastern provinces (now known as Region 5) until decades later. Sistani began his religious education as a child, first in Mashhad in his father's hawzah, and continuing later in Qom. In 1951, Sistani traveled to Iraq to study in Najaf under Grand Ayatollah Abu al-Qasim al-Khoei. Sistani rose to the Usooli clerical rank of 'mujtahid' in 1960.[2] At the unusually young age of thirty-one, Sistani reached the senior level of clerical accomplishment, or ijtihad, which entitled him to pass his own judgments on religious questions.[3]

When Grand Ayatollah Khoei died in 1992, Sistani ascended to the rank of Grand Ayatollah through traditional peer recognition of his scholarship. His role as successor to Khoei was symbolically cemented when he led funeral prayers for Khoei; he also inherited Khoei's network and following.

During the years of Saddam Hussein's rule of Iraq through the Ba'ath Party, Sistani was untouched during the violent Ba'athist repression and persecution that killed many clerics. His predecessor, Khoei, often sat down with Saddam on state tv and showed subordination to him. After the deaths of several leading clerics in Iraq, including Grand Ayatollah Mohammad Mohammad Sadeq al-Sadr, Sistani emerged as the prominent Shia cleric, although Sistani's mosque was shut down in 1994, and did not reopen until the US-led 2003 invasion of Iraq.

Since the overthrow of the Ba'ath Party, Sistani has played an increasingly prominent role in regional religious and political affairs and he has been called the "most influential" figure in post-invasion Iraq.[4][5]

Shortly after the US invasion began, Sistani issued a fatwa advising Shia clergy to become engaged in politics in order to better guide the Iraqi people toward "clearer decisions," and to fight "media propaganda."[citation needed] As the summer of 2003 approached, Sistani and his followers began to petition the occupying forces for a constitutional convention. Later, Sistani called for a democratic vote of the people for the purpose of forming a transitional government. Observers described the move as being a path leading directly to Shia political dominance over Iraq's government, as Shia Muslims make up approximately 60% of the total Iraqi population.[citation needed] Subsequently, Sistani criticized plans for an Iraqi government for not being democratic enough.[citation needed]

In early August, 2004, Sistani experienced serious health complications related to a previously diagnosed heart condition. He traveled to London to receive medical treatment. It was, reportedly, the first time that Sistani had left Iraq in decades, and may have been due, in part, to growing concerns for his safety from sectarian violence. Though still recovering, Sistani returned later in the month to broker a military truce at the Imam Ali Mosque in Najaf where Sheik Muqtada al-Sadr and the Mahdi Army had been cornered by American and Iraqi forces. Sadr, who rose rapidly to prominence through a series of independent military actions beginning in 2004, has since actively challenged Sistani's more progressive influence over Shia in the region.[6]

Sistani's edicts reportedly provided many Iraqi Shia cause for participating in the January 2005 elections—he urged, in a statement on October 1, 2004, that Iraqis recognize the election as an "important matter," additionally, Sistani asked that the elections be "free and fair. . . with the participation of all Iraqis." Soon after, Sistani issued a fatwa alerting Shia women that they were religiously obligated to participate in the election, even if their husbands had forbidden them from voting.[7] In an issued statement Sistani remarked that, "truly, women who go forth to the polling centers on election day are like Zaynab, who went forth to Karbala."[8]

He has consistently urged the Iraqi Shia not to respond in kind to attacks from SunniSalafists, which have become common in Sunni-dominated regions of Iraq like the area known as the "Triangle of Death," south of Baghdad. Even after the destruction of the Shia Al-Askari Mosque in Samarra in February 2006, his network of clerics and preachers continued to urge calm and told their followers that "it was not their Sunni neighbors who were killing them but foreign Wahhabis." [9]

An alleged plot to assassinate Sistani was foiled on January 29, 2007, when three Jund al-Samaa gunmen were captured at a hotel near his office. It is believed to have been part of a larger attack against a number of targets in Najaf.[10]

As the leading Ayatollah in Najaf, Sistani oversees sums amounting to millions of US dollars. Sistani's followers offer him a fixed part of their earnings (tithe), which is used for educational and charitable purposes. Sistani's office has reported that it supports 35,000 students in Qom, 10,000 in Mashhad, and 4,000 in Isfahan.[13] It also oversees a network of representatives (wakil) "who promote his (Sistani's) views in large and small ways in neighborhoods, mosques, bazaars, and seminaries from Kirkuk to Basra."[14]

Additionally, Sistani has a substantial following within Shia communities all over the world and is the current Nayb-i Imam (Preeminent Marja) of the Twelver sect of Shia Muslims. In Iran, as a result of the post-invasion opening of the Iraqi cities of Najaf and Karbala to Iranians, many Iranians are said to return from pilgrimage in Iraq as supporters of Sistani.[15]

In May 2007, hundreds of Shias demonstrated publicly in Basra and Najaf to protest comments made by television presenter and journalist Ahmed Mansour during a Qatari broadcast of Al Jazeera television programming. While presenting Bela Hodod (a.k.a. Without Borders), Mansour voiced skepticism of Sistani's leadership credentials while directing questions about the Iranian-born cleric to his guest, ShiaclericJawad al-Khalsi. Mansour also suggested that Sistani was not aware of contemporary problems in Iraq or of prevailing post-war conditions, and he alleged that Sistani's edicts were, largely, written and disseminated by aides. At another point, Mansour asked Khalsi whether the United States was using Iraqi politicians, and also Sistani, to promote western interests in Iraq.[16]

In January 2010, during a Jumu'ahkhutba (Friday sermon), Saudi cleric Mohamad al-Arefe vehemently criticized Sistani by referring to him as an "atheist" and by describing his behavior as "debauched".[17] The remarks were considered extremely offensive, prompting outraged protest by his followers in Iraq, Qom and Lebanon. Iraqi Prime Minister Nouri al-Maliki rebuked the Saudi religious authorities.[18] Lebanon-based Islamist militant organization Hezbollah also condemned the attack on Sistani, calling the speech "inauspicious," while praising Sistani as one of Shia Islam's "most prominent religious references."[19]

On 4 March 2014, the Daily Telegraph commentator Colin Freeman published an article[20] naming Ali al-Sistani as the most appropriate Nobel Peace Prize candidate. He also reported that he had been nominated earlier in 2006, by a group of Iraqi Christians.

On 8 March 2014, The Tehran Times[21] reported that a group of members of Iraqi parliament announced that they intend to nominate Ali al-Sistani for the 2014 Nobel Peace Prize.

Like his predecessor Abu al-Qasim al-Khoei, Sistani has not wholly embraced the post-Age-of-Occultation theory known as the Guardianship of the Islamic Jurists, which was espoused and supported by the late Iranian Grand Ayatollah Ruhollah Khomeini and which is currently extant and enforced by the Iranian government through its own constitution and by its supreme leader and highest religious authority Ayatollah Ali Khamenei. Sistani's scholarship regarding guardianship resembles Khoei's scholarship, but differs in several respects. Additionally, the primary difference between Sistani's interpretation and the interpretation of Grand Ayatollahs Khomeini and Khamenei is reportedly in the range of power that a Grand Ayatollah has in ruling the Islamic community. Sistani has publicly stated and maintained that his interpretation of doctrine is one that grants more power to the Ayatollahs than Khoei, but less than either Khoemeini or Khamenei:

Question: What is Grand Ayatollah Sistani's opinion about Velayat-e Faqih?

Answer: Every jurisprudent (Faqih) has wilayah (guardianship) over non-litigious affairs. Non-litigious affairs are called "al-omour al-hesbiah." As for general affairs to which social order is linked, and enforcement of doctrine, this depends on certain conditions, one of which is popularity of the Faqih among the majority of momeneen (believers).[23]

On the specific question of obedience to a Supreme Leader, Sistani has said that any pronouncement given by a Supreme Leader "supersedes all, (including those given by other Maraji') unless the pronouncements are proven to be wrong or the pronouncements are proven to be against what is in the Qur'an or in Religious Tradition."[24]

Additionally, instead of advocating for rule by Islamic clerics or for fundamentalist legal views, i.e. "the Quran as constitution," Sistani is said to favor a more relaxed perspective related to the provision of values and guidelines for social order (nizam al-mujama) as being the recognized, primary role of Islam.[25]

Also, according to Sadegh Zibakalam, professor of political science at Tehran University, Sistani has consistently avoided supporting strict interpretation of the theory, especially of absolute guardianship, nor has he explicitly offered any substantive affirmation of the theory as a whole (including limited guardianship); thereby creating "a major lacuna" in the "grand ideological scenario" of the Islamic Republic of Iran.[26]

According to scholar Vali Nasr, despite Sistani's disagreements with Iran's ruling clerics, he has "never tried to promote a rivalry" between his religious center of Najaf and the Iranian center in Qom, and has never made any comments about the confrontations between reformists and conservatives in Qom or between clerics in Lebanon,[27] a reflection, Nasr believes, of Sistani's reluctance to become involved in politics.

After the attack, visitors to the site were greeted by a red attack banner bearing the slogan "group-xp" paired with a message in Arabic denouncing Shia beliefs and officials. Hackers also replaced a video of Sistani with one of comedian Bill Maher mocking Sistani.[31]

However, the attack led to the hacking of more than nine hundred Wahhabi and Salafi websites.[32] One such successful attack was documented on video and uploaded to YouTube on October 3, 2008. The hacker, a Shia from the United Arab Emirates using the handle "ShiaZone," was shown logging into email accounts of suspected members of group-xp. The hacked email accounts reportedly yielded group-xp's contact information, information that was subsequently posted on Shia websites.[33]

^"Shiite Cleric Seen as Iraq's Most Influential Leader". pub. November 27, 2003. Retrieved 2007-08-21. a frail, 70-something Shiite Muslim (search) cleric with a heart condition — has emerged in post-Saddam Hussein Iraq as the land's most influential figure, something US planners may not have counted on.